package com.appgemacht.postinews.util;

import android.annotation.TargetApi;
import android.app.Activity;
import android.os.Build;
import android.view.View;
import android.view.WindowManager;

/**
 * An API 11+ implementation of {@link SystemUiHider}. Uses APIs available in
 * Honeycomb and later (specifically {@link View#setSystemUiVisibility(int)}) to
 * show and hide the system UI.
 */
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public class SystemUiHiderHoneycomb extends SystemUiHiderBase {
  /**
   * Flags for {@link View#setSystemUiVisibility(int)} to use when showing the
   * system UI.
   */
  private int mShowFlags;

  /**
   * Flags for {@link View#setSystemUiVisibility(int)} to use when hiding the
   * system UI.
   */
  private int mHideFlags;

  /**
   * Flags to test against the first parameter in
   * {@link android.view.View.OnSystemUiVisibilityChangeListener#onSystemUiVisibilityChange(int)}
   * to determine the system UI visibility state.
   */
  private int mTestFlags;

  /**
   * Whether or not the system UI is currently visible. This is cached from
   * {@link android.view.View.OnSystemUiVisibilityChangeListener}.
   */
  private boolean mVisible = true;

  /**
   * Constructor not intended to be called by clients. Use
   * {@link SystemUiHider#getInstance} to obtain an instance.
   */
  protected SystemUiHiderHoneycomb(Activity activity, View anchorView, int flags) {
    super(activity, anchorView, flags);

    mShowFlags = View.SYSTEM_UI_FLAG_VISIBLE;
    mHideFlags = View.SYSTEM_UI_FLAG_LOW_PROFILE;
    mTestFlags = View.SYSTEM_UI_FLAG_LOW_PROFILE;

    if ((mFlags & FLAG_FULLSCREEN) != 0) {
      // If the client requested fullscreen, add flags relevant to hiding
      // the status bar. Note that some of these constants are new as of
      // API 16 (Jelly Bean). It is safe to use them, as they are inlined
      // at compile-time and do nothing on pre-Jelly Bean devices.
      mShowFlags |= View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN;
      mHideFlags |= View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
          | View.SYSTEM_UI_FLAG_FULLSCREEN;
    }

    if ((mFlags & FLAG_HIDE_NAVIGATION) != 0) {
      // If the client requested hiding navigation, add relevant flags.
      mShowFlags |= View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;
      mHideFlags |= View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
          | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
      mTestFlags |= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
    }
  }

  /** {@inheritDoc} */
  @Override
  public void setup() {
    mAnchorView
        .setOnSystemUiVisibilityChangeListener(mSystemUiVisibilityChangeListener);
  }

  /** {@inheritDoc} */
  @Override
  public void hide() {
    mAnchorView.setSystemUiVisibility(mHideFlags);
  }

  /** {@inheritDoc} */
  @Override
  public void show() {
    mAnchorView.setSystemUiVisibility(mShowFlags);
  }

  /** {@inheritDoc} */
  @Override
  public boolean isVisible() {
    return mVisible;
  }

  private View.OnSystemUiVisibilityChangeListener mSystemUiVisibilityChangeListener = new View.OnSystemUiVisibilityChangeListener() {
    @Override
    public void onSystemUiVisibilityChange(int vis) {
      // Test against mTestFlags to see if the system UI is visible.
      if ((vis & mTestFlags) != 0) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
          // Pre-Jelly Bean, we must manually hide the action bar
          // and use the old window flags API.
          mActivity.getActionBar().hide();
          mActivity.getWindow().setFlags(
              WindowManager.LayoutParams.FLAG_FULLSCREEN,
              WindowManager.LayoutParams.FLAG_FULLSCREEN);
        }

        // Trigger the registered listener and cache the visibility
        // state.
        mOnVisibilityChangeListener.onVisibilityChange(false);
        mVisible = false;

      } else {
        mAnchorView.setSystemUiVisibility(mShowFlags);
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
          // Pre-Jelly Bean, we must manually show the action bar
          // and use the old window flags API.
          mActivity.getActionBar().show();
          mActivity.getWindow().setFlags(0,
              WindowManager.LayoutParams.FLAG_FULLSCREEN);
        }

        // Trigger the registered listener and cache the visibility
        // state.
        mOnVisibilityChangeListener.onVisibilityChange(true);
        mVisible = true;
      }
    }
  };
}
